Hallucinogenic Drugs

Abstract

Hallucinogens constitute one of the oldest classes of drugs used by humanity, often in the context of spiritual practices.
Classic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin, N,N‐dimethyltryptamine (DMT), mescaline and 2,5‐dimethoxy‐4‐methylamphetamine (DOM) produce complex psychological and physical
effects, including perceptual changes, cognitive shifts in reality and emotional alterations. These drugs primarily act on
serotonin systems through 5‐hydroxytryptamine 2A (5HT2A) receptors, with additional activity through dopamine and glutamate systems. Investigation of the neurochemical and behavioural
effects of this class of drugs has provided important insights into pharmacology and psychiatric conditions. Given their popularity
as recreational drugs, investigation of their actions and effects continues to be an important endeavour. After a long hiatus,
clinical studies in humans have resumed with these drugs in laboratories around the world.

Key Concepts:

Hallucinogens have been used for thousands of years by various societies, often in conjunction with spiritual practices.

In present day, hallucinogens remain highly popular as recreational drugs.

The chemical structure of hallucinogens consists of tryptamines (LSD and psilocybin) and phenethylamines (mescaline and DOM).

The potency of hallucinogens is directly correlated to their ability to act as agonists at the serotonin receptor subtype,
5‐HT2A.

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